Constipation generally means that you have three or fewer bowel movements a week.

But it can also mean straining to have bowel movements or passing stools that are small, hard, and dry. The good news is that it's easy to treat constipation, and even easier to prevent it — as long as you know its causes.

Causes of Constipation: Lifestyle and Diet

Poor diet and an inactive lifestyle are the most common causes of constipation. A lack of exercise and eating too much junk food can wreak havoc on your digestive health. Here are some diet-related factors that can leave you feeling constipated:

Changes to your normal routine can also cause problems with your digestive system, resulting in constipation because of sporadic access to bathrooms, lack of exercise, and changes in diet.

So when you're traveling, try to be consistent and keep eating lots of healthy, high-fiber foods, exercising, and drinking water.

Causes of Constipation: Medications

Constipation is a common side effect of many frequently prescribed medications. If you've just started taking a new drug and notice that your bowel movements have changed in form or frequency, ask your doctor if your medication could be the cause.

Some common medications that can cause constipation are diuretics, antacids (with aluminum and calcium), narcotics, antidepressants, supplements, anticonvulsants, and blood pressure treatments.

Constipation can also be caused by the very medications taken to treat them — laxatives. Americans spend more than $700 million on these constipation treatments annually, but just like some other over-the-counter and prescribed medications, laxatives can become habit-forming. Taking them too often may cause your digestive system to become too dependent on them.

Causes of Constipation: Health Conditions

Constipation can also be a side effect or symptom of many health conditions. These conditions can cause stool to pass more slowly through the colon, resulting in constipation.

Irritable bowel syndrome (IBS), also known as spastic colon, is one of the most common causes of constipation. Not much is known about what causes this digestive disorder, but medical researchers believe that IBS patients have highly sensitive colons and must therefore monitor what they eat.

Aging can also trigger constipation, so preventive steps to keep your bowel movements regular should be taken.

There are other conditions that can cause constipation. Talk with your doctor to get more personalized information and find out if your constipation is a side effect of another health problem. It is also a good idea to check with your doctor if there is a significant change in your bowel habits.

Constipation can be uncomfortable to talk about, but even more uncomfortable to deal with. So take a close look at your daily habits and lifestyle and see if you can pinpoint what might be causing your constipation. A healthy body means healthy digestion — feeling great inside and out.